Design of a Low-Frequency Enclosed Differential Driver-Pickup Eddy-Current Sensor for Surface Defect Detection in Reformer Tubes
Journal
2026 IEEE International Magnetic Conference-Short Papers, INTERMAG Short Papers 2026 - Proceedings
Start Page
1
End Page
2
ISBN (of the container)
979-833155762-1
Date Issued
2026-04-13
Author(s)
Abstract
This paper presents a low-frequency, enclosed differential driver-pickup eddy-current sensor for surface defect detection in HP-40 Mod Nb reformer tubes used in petrochemical plants. HP-40 Mod Nb is a metal characterized by low conductivity and permeability. The proposed differential coil configuration effectively suppresses environmental noise while significantly enhancing surface crack sensitivity. Finite element simulations were conducted to optimize the sensor geometry and evaluate its defect-detection performance. An automated rotational-scanning platform operating at a constant speed was developed to experimentally validate the simulation results. A high-pass filtering and curve-fitting approach was further employed to extract the defect signal and estimate depth. Experimental results demonstrate that the proposed system accurately characterizes surface defects with depths greater than 0.5 mm, achieving an estimation error of 2.13%, indicating its strong potential for practical non-destructive inspection of petrochemical reformer tubes.
Event(s)
2026 IEEE International Magnetic Conference - Short Papers, INTERMAG Short Papers 2026,13 April 2026 - 17 April 2026,Manchester
Subjects
defect detection
Eddy current sensor
non-destructive testing
reformer tubes
Publisher
IEEE
Type
conference paper